An essential requirement for the operation of integrated circuits is the transfer of heat generated by the integrated circuit chip from the package itself to the external environment. The problem of heat dissipation is especially acute in high density packaging applications where the volume allotment for heat exchange media is extremely limited.
Commonly used heat exchange or heat sink devices for integrated circuit packages result from extrusions, stampings, and machined parts formed in a variety of shapes and configurations. However, because of size and volume constraints, none of these manufacturing methods yield devices which offer maximum effective cooling area for a given volume. The latter criterion is a prime factor in overall heat exchanger performance. Related to the effective cooling area of the device is its heat transfer coefficient factor. Here again, the above-mentioned devices do not maximize this characteristic. It is apparent that the heat that is transferred from the package to the ambient must overcome the thermal resistance of the heat exchanger itself. The largest component of the total resistance offered by the heat exchange device is designated film resistance and is inversely proportional to the surface area of the device. Stated another way, film resistance is the reciprocal of the product of the effective surface area and the convective heat transfer coefficient. Maximizing the latter factors, reduces the film resistance of the heat exchanger.
The present element accomplishes the foregoing with a simple, economical, volume effective structure. As compared with the device of the reference application, the present heat exchange element is even easier and less costly to manufacture, thereby further increasing its attractiveness in applications such as large scale computer systems, where considerable numbers of the elements are required.